---
title: kind
description: This setting tells the pattern what pattern type to match. Acceptable values for this setting are prefix, suffix, timestring, and regex. There is no default...
url: https://www.elastic.co/elastic/docs-builder/docs/3028/reference/elasticsearch/curator/fe_kind
products:
  - Elasticsearch
  - Elasticsearch Curator
---

# kind
<note>
  This setting is only used with the [pattern](https://www.elastic.co/elastic/docs-builder/docs/3028/reference/elasticsearch/curator/filtertype_pattern) filtertype and is a required setting.
</note>

This setting tells the [pattern](https://www.elastic.co/elastic/docs-builder/docs/3028/reference/elasticsearch/curator/filtertype_pattern) what pattern type to match. Acceptable values for this setting are `prefix`, `suffix`, `timestring`, and `regex`.
<admonition title="Filter chaining">
  It is important to note that while filters can be chained, each is linked by an implied logical **AND** operation.  If you want to match from one of several different patterns, as with a logical **OR** operation, you can do so with the [pattern](https://www.elastic.co/elastic/docs-builder/docs/3028/reference/elasticsearch/curator/filtertype_pattern) filtertype using *regex* as the `kind`.This example shows how to select multiple indices based on them beginning with either `alpha-`, `bravo-`, or `charlie-`:
  ```yaml
    filters:
    - filtertype: pattern
      kind: regex
      value: '^(alpha-|bravo-|charlie-).*$'
  ```
  Explaining all of the different ways in which regular expressions can be used is outside the scope of this document, but hopefully this gives you some idea of how a regular expression pattern can be used when a logical **OR** is desired.
</admonition>

There is no default value. This setting must be set by the user or an exception will be raised, and execution will halt.
The different `kinds` are described as follows:

## prefix

To match all indices starting with `logstash-`:
```yaml
- filtertype: pattern
 kind: prefix
 value: logstash-
```

To match all indices *except* those starting with `logstash-`:
```yaml
- filtertype: pattern
 kind: prefix
 value: logstash-
 exclude: True
```

<note>
  Internally, the `prefix` value is used to create a *regex* pattern: `^{{0}}.*$`. Any special characters should be escaped with a backslash to match literally.
</note>


## suffix

To match all indices ending with `-prod`:
```yaml
- filtertype: pattern
 kind: suffix
 value: -prod
```

To match all indices *except* those ending with `-prod`:
```yaml
- filtertype: pattern
 kind: suffix
 value: -prod
 exclude: True
```

<note>
  Internally, the `suffix` value is used to create a *regex* pattern: `^.*{{0}}$`. Any special characters should be escaped with a backslash to match literally.
</note>


## timestring

<important>
  No age calculation takes place here. It is strictly a pattern match.
</important>

To match all indices with a Year.month.day pattern, like `index-2017.04.01`:
```yaml
- filtertype: pattern
 kind: timestring
 value: '%Y.%m.%d'
```

To match all indices *except* those with a Year.month.day pattern, like `index-2017.04.01`:
```yaml
- filtertype: pattern
 kind: timestring
 value: '%Y.%m.%d'
 exclude: True
```

<admonition title="A word about regular expression matching with timestrings">
  Timestrings are parsed from strftime patterns, like `%Y.%m.%d`, into regular expressions.  For example, `%Y` is 4 digits, so the regular expression for that looks like `\d{{4}}`, and `%m` is 2 digits, so the regular expression is `\d{{2}}`.What this means is that a simple timestring to match year and month, `%Y.%m` will result in a regular expression like this: `^.*\d{{4}}\.\d{{2}}.*$`.  This pattern will match any 4 digits, followed by a period `.`, followed by 2 digits, occurring anywhere in the index name.  This means it *will* match monthly indices, like `index-2016.12`, as well as daily indices, like `index-2017.04.01`, which may not be the intended behavior.To compensate for this, when selecting indices matching a subset of another pattern, use a second filter with `exclude` set to `True`
  ```yaml
  - filtertype: pattern
   kind: timestring
   value: '%Y.%m'
  - filtertype: pattern
   kind: timestring
   value: '%Y.%m.%d'
   exclude: True
  ```
  This will prevent the `%Y.%m` pattern from matching the `%Y.%m` part of the daily indices.**This applies whether using `timestring` as a mere pattern match, or as part of date calculations.**
</admonition>


## regex

This `kind` allows you to design a regular-expression to match indices or snapshots:
To match all indices starting with `a-`, `b-`, or `c-`:
```yaml
- filtertype: pattern
 kind: regex
 value: '^a-|^b-|^c-'
```

To match all indices *except* those starting with `a-`, `b-`, or `c-`:
```yaml
- filtertype: pattern
 kind: regex
 value: '^a-|^b-|^c-'
 exclude: True
```